The diffusion of 3He in the live guinea pig lung will be studied with various methods. The time evolution of a slice profile will give an average measure of the diffusion with 2D spatial localization. Diffusion weighted imaging with radial acquisition will give another average measure. Spectroscopic studies with spatially selective RF pulses should give more quantitative data. In addition, measurements of T2* will be accomplished by taking successive projection reconstruction images and varying the acquisition delay.